How did Martin Heidegger connect time with human existence?

In his seminal work Being and Time, Martin Heidegger rejected the traditional view of human existence as a static, "thing-like" entity. Instead, he argued that human existence, or Dasein, is fundamentally defined by its temporality (Zeitlichkeit).1

Heidegger connected time to human existence through the following key concepts:

• Ecstatic Orientation: Unlike objects that are merely "present-at-hand," Dasein is "ecstatically" oriented toward its own future possibilities. This means human existence is always "out ahead of itself," actively projecting itself into the future rather than existing as a passive, sequential progression of moments.12
• Historicity: Heidegger argued that Dasein "temporalizes" as part of a larger social and historical collective. This means individuals possess a heritage and must make conscious decisions about how to actualize their lives. True existence involves responding to the collective past, in the context of the present, for the sake of the future.1
• Being-toward-death: A central aspect of authentic existence is the confrontation with one's own finitude. By acknowledging the inevitability of death, Dasein moves away from the inauthentic distractions of "the They" (das Man) and fulfills its potential for being a self.13